This invention relates to a mattress construction having different degrees of firmness; more particularly, the present invention aims at providing an improved degree of comfort to the user, inasmuch as it is known that, for a correct anatomical posture, it is required that the trunk and the thighs of the user have more yieldable support than the head and the feet.
Thus, the principal object of the present invention is to provide an improved mattress construction in which the firmness or resiliency of the central transverse section of a mattress of the kind having an array of coil springs in its inside, can be varied according to the user's needs and within a reasonably wide range.
Another important object of the present invention is to improve the internal structure of a spring mattress by providing a sort of three-membered skeleton comprising a top border wire, a bottom border wire, and a center wire therebetween, the latter being slightly internally offset with respect to the top and the bottom border wires. The top, bottom and center wire preferably have a substantially rectangular outline, consistent with the usual rectangular shape of a mattress construction. The function of such a three-membered skeleton is to hold the outer canvas cover of the mattress securely in position.
Still another object of the present invention is to provide an improved handle structure for an innerspring mattress, enabling the user conveniently to manipulate the mattress without any risk of damaging the fabric cover of the mattress.